Added events to notify before/after tile rendering.

CHANGES.rst

@@ -4,6 +4,16 @@ Changelog
 4.1.2 (unreleased)
 ------------------
 
+Breaking changes:
+
+- *add item here*
+
+New features:
+
+- Added events to notify before/after tile rendering.
+  [thet]
+
+
 Bug fixes:
 
 - Fix issue where resolving layout url with ajax_load parameter caused fail

plone/app/blocks/events.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+from plone.app.blocks.interfaces import IAfterTileRenderEvent
+from plone.app.blocks.interfaces import IBeforeTileRenderEvent
+from zope.interface import implementer
+
+
+class BaseTileRenderEvent(object):
+
+    def __init__(self, tile_href):
+        self.tile_href = tile_href
+
+
+@implementer(IBeforeTileRenderEvent)
+class BeforeTileRenderEvent(BaseTileRenderEvent):
+    pass
+
+
+@implementer(IAfterTileRenderEvent)
+class AfterTileRenderEvent(BaseTileRenderEvent):
+    pass

plone/app/blocks/interfaces.py

@@ -2,6 +2,7 @@
 from plone.resource.manifest import ManifestFormat
 from zope import schema
 from zope.i18nmessageid import MessageFactory
+from zope.interface import Attribute
 from zope.interface import Interface
 
 
@@ -83,3 +84,19 @@ def __unicode__():
 
     def __str__():
         """Return the layout as a str value"""
+
+
+class IBaseTileRenderEvent(Interface):
+    """Base class for tile render events.
+    """
+    tile_href = Attribute('URL of the rendered tile')
+
+
+class IBeforeTileRenderEvent(IBaseTileRenderEvent):
+    """Thrown before a tile is rendered.
+    """
+
+
+class IAfterTileRenderEvent(IBaseTileRenderEvent):
+    """Thrown after a tile is rendered.
+    """

plone/app/blocks/tiles.py

@@ -1,6 +1,7 @@
 # -*- coding: utf-8 -*-
 from lxml import html
 from lxml.etree import XSLTApplyError
+from plone.app.blocks import events
 from plone.app.blocks import PloneMessageFactory
 from plone.app.blocks import utils
 from plone.app.blocks.interfaces import IBlocksSettings
@@ -11,6 +12,7 @@
 from urlparse import urljoin
 from zExceptions import NotFound
 from zope.component import queryUtility
+from zope.event import notify
 from zope.i18n import translate
 
 import logging
@@ -48,6 +50,8 @@ def renderTiles(request, tree):
         tileHref = tileNode.attrib[utils.tileAttrib]
         if not tileHref.startswith('/'):
             tileHref = urljoin(baseURL, tileHref)
+
+        notify(events.BeforeTileRenderEvent(tileHref))
         try:
             tileTree = utils.resolve(tileHref)
         except RuntimeError:
@@ -62,13 +66,16 @@ def renderTiles(request, tree):
         if tileTree is not None:
             tileRoot = tileTree.getroot()
             utils.replace_with_children(tileNode, tileRoot.find('head'))
+        notify(events.AfterTileRenderEvent(tileHref))
 
     for tileNode in utils.bodyTileXPath(tree):
         tileHref = tileNode.attrib[utils.tileAttrib]
         tileRulesHref = tileNode.attrib.get(utils.tileRulesAttrib)
 
         if not tileHref.startswith('/'):
             tileHref = urljoin(baseURL, tileHref)
+
+        notify(events.BeforeTileRenderEvent(tileHref))
         try:
             tileTree = utils.resolve(tileHref)
         except RuntimeError:
@@ -109,5 +116,6 @@ def renderTiles(request, tree):
                 for tileHeadChild in tileHead:
                     headNode.append(tileHeadChild)
             utils.replace_with_children(tileNode, tileBody)
+        notify(events.AfterTileRenderEvent(tileHref))
 
     return tree